JP2011137192A - Cleaning agent for metal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning agent for metal which has high cleaning property to metal, corrosion resistance and resistance to discoloration and excellent in foam inhibiting property and liquid state stability in a highly concentrated liquid. <P>SOLUTION: The cleaning agent for metal contains (A) component: a specific nonionic surfactant; (B) component: a specific amine component; (C) component: a salt of a 4-10C (in total) carboxylic acid; (D) component: a silicate; (E) component: a hydroxide of an alkali metal. The contents of the components (A), (B), (C), (D) and (E) are, by mass, 5-30%, 1-10%, 5-20%, 1-3% and 2-6%, respectively. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a metal cleaning agent for cleaning a metal such as aluminum.

Generally, when pressing a metal, a lubricating oil is used to improve the lubricity between the metal and the mold. Further, when cutting and polishing metal, cutting oil is used to remove frictional heat generated during processing.
In addition to the above lubricating oil and cutting oil, metal chips obtained by metalworking have cutting scraps and polishing scraps attached. If these are used while they are attached, the performance and quality of the resulting metal product will be reduced. May cause a drop. Therefore, it usually has a step of cleaning metal parts using a cleaning agent after processing.
High alkaline detergents are widely used because they are excellent in cleaning metal parts. However, when the metal is an amphoteric metal such as aluminum, it is alkaline and corrosion proceeds. Therefore, for the amphoteric metal, the use of a highly alkaline detergent is avoided, and a detergent having anticorrosive properties is used.
As a metal detergent having anticorrosive properties, Patent Document 1 discloses a detergent containing a carboxylic acid or a salt thereof, a higher alkylamine, and a nonionic surfactant. Patent Document 2 discloses a cleaning agent containing a carboxylic acid, an alkanolamine, and a diamine.

By the way, in the cleaning process, the cleaning agent is often sprayed onto the metal by spraying. However, when the spraying is used, the cleaning agent tends to foam. Moreover, when the surfactant is included in the cutting oil, the cleaning liquid after cleaning becomes more easily foamed. When foaming occurs, workability deteriorates, and thus the cleaning agent is required to have high antifoaming properties. However, the cleaning agents described in Patent Documents 1 and 2 cannot be said to have high antifoaming properties. Moreover, the cleaning and anticorrosion properties were not sufficient.
As a detergent having high antifoaming properties, Patent Document 3 discloses a detergent containing amines, surfactants and glycol ethers. However, the cleaning agent described in Patent Document 3 has not had sufficient cleaning properties for metals.
Furthermore, it was difficult for the cleaning agents described in Patent Documents 1 to 3 to ensure liquid stability when a high concentration liquid was used.

JP-A-8-319499 Japanese Patent No. 2923410 Japanese Patent No. 2899784

  An object of the present invention is to provide a metal cleaning agent that has high detergency against metals, anticorrosion, and anti-discoloration properties, has excellent antifoaming properties, and excellent liquid stability when used as a high concentration liquid. And

[1] Component (A): General Formula (1) R ¹ O (AO) _n H (wherein R ¹ is an alkyl group or alkenyl group having 8 to 11 carbon atoms, AO is an alkylene oxide, and n is AO) Nonionic surfactant represented by the following formula:
Component (B): an amine compound represented by general formula (2) R ² —X— (CH ₂ ) ₃ —NH ₂ (wherein R ² is an alkyl group having 8 to 12 carbon atoms, and X is -O- or -NH-).
Component (C): a carboxylic acid salt having 4 to 10 carbon atoms in total,
(D) component: silicate,
(E) component: containing an alkali metal hydroxide,
The content of the component (A) is 5 to 30% by mass, the content of the component (B) is 1 to 10% by mass, the content of the component (C) is 5 to 20% by mass, and the content of the component (D) is 1 to 3% by mass, and (E) component content is 2 to 6% by mass.
[2] The metal cleaning agent according to [1], wherein the molar ratio (C / E) of the component (C) to the component (E) is 0.5 to 2.5.

  The metal detergent of the present invention has high detergency against metals, anticorrosion, and discoloration prevention, and is excellent in antifoaming properties and liquid stability when made into a high concentration liquid.

  The metal cleaning agent of the present invention (hereinafter abbreviated as “cleaning agent”) includes (A) component: nonionic surfactant, (B) component: amine compound, and (C) component: carboxylic acid salt. , (D) component: Silicate and (E) component: Alkali metal hydroxide.

[(A) component: nonionic surfactant]
The nonionic surfactant as component (A) is a compound represented by the following general formula (1), and imparts detergency while having antifoaming properties.
Formula (1) R ¹ O (AO) _n H
In the general formula (1), R ¹ is an alkyl group or an alkenyl group having 8 to 11 carbon atoms, preferably 8 to 10 carbon atoms. When R ¹ has 8 or more carbon atoms, it has excellent cleaning properties, and when it has 11 or less carbon atoms, it becomes easy to handle.
AO in the general formula (1) is an alkylene oxide (one or both of ethylene oxide (EO) and propylene oxide (PO)). When the alkylene oxide is EO, the detergency is improved, and when it is PO, it has the effect of enhancing the foam suppression property during the washing. In the case of having both EO and PO, the added form may be a block or random.
n is the average added mole number of AO and is 1 to 10, preferably 3 to 5. When n is 1 or more, the detergency is excellent, and when it is 10 or less, the defoaming property at the time of cleaning is excellent.

  (A) Content of nonionic surfactant of a component is 5-30 mass% when the whole washing | cleaning agent is 100 mass%, and it is preferable that it is 15-20 mass%. When the content of the nonionic surfactant is 5% by mass or more, the detergency becomes high, and when it is 30% by mass or less, sufficient liquid stability can be secured, and each of (A) to (E) A sufficient amount of ingredients can be blended.

[(B) component: amine compound]
The amine compound as the component (B) is a compound represented by the following general formula (2), and improves detergency and foam suppression.
Formula ^{(2) R 2 -X- (CH} 2) 3 -NH 2

Specifically, the compound represented by the general formula (2) is an alkyldiamine or an alkyloxoamine.
In general formula (2), R ² is an alkyl group having 8 to 12 carbon atoms, preferably 9 to 11 carbon atoms. When the carbon number of R ² of the component (B) is 8 or more, the cleaning property and foam suppression property are enhanced, and an adsorption film can be easily formed, and the corrosion resistance is enhanced. On the other hand, when the carbon number of R ^{2 in} the component (B) is 12 or less, the foam suppression property is enhanced.
X in Formula (2) is —O— or —NH—, but —O— is preferable in terms of higher corrosion resistance.
In addition, the amine compound is preferably an alkyl oxoamine, more preferably an alkyl oxamine having 9 to 11 carbon atoms of R ² in that the amine compound has a large polarity and is difficult to foam.

  (B) Content of the amine compound of a component is 1-10 mass% when the whole cleaning agent is 100 mass%, and it is preferable that it is 3-6 mass%. When the content of the amine compound is 1% by mass or more, the antifoaming property is increased, and when it is 10% by mass or less, the liquid stability that can be a high concentration liquid can be ensured.

[(C) component: carboxylate]
The carboxylate of component (C) is a salt of a carboxylic acid having 4 to 10 carbon atoms. These carboxylates impart anticorrosive properties to the metal.
When the total carbon number of the (C) component carboxylate is 4 or more, the anticorrosion property is increased, and when the total carbon number is 10 or less, the antifoaming property is increased.

Examples of the carboxylic acid having 4 to 10 carbon atoms include butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, and succinic acid.
Bases for salt formation include inorganic bases such as sodium, potassium, calcium, magnesium, ammonia, methylamine, dimethylamine, ethylamine, diethylamine, (iso) propylamine, di (iso) propylamine, monoethanolamine , Organic bases such as N-methylmonoethanolamine, N-ethylmonoethanolamine, diethanolamine, triethanolamine, monopropanolamine, dipropanolamine, and tripropanolamine. As the carboxylate, a carboxylate previously prepared may be added when preparing the cleaning agent, or the carboxylic acid and the base may be added separately when preparing the cleaning agent.
Among carboxylates, n-octanoate is preferable and sodium n-octanoate is more preferable because higher anticorrosive properties can be obtained.

  (C) Content of the carboxylate of a component is 5-20 mass% when the whole washing | cleaning agent is 100 mass%, and it is preferable that it is 10-15 mass%. When the content of the carboxylate of component (C) is 5% by mass or more and 20% by mass or less, the liquid stability when a high-concentration liquid is obtained increases.

[(D) component: silicate]
(D) The silicate of a component is for improving corrosion resistance.
Specific examples of the silicate include sodium silicate, layered sodium silicate, sodium metasilicate, sodium orthosilicate and the like, and sodium metasilicate is preferable.
The molar ratio (SiO ₂ / Na ₂ O) between Na ₂ O and SiO ₂ in the silicate is not particularly limited, and the molar ratio (SiO ₂ / Na ₂ O) is 0.3 to 3.0. Preferably, it is 0.5 to 2.0, more preferably 0.7 to 1.5.
More preferable silicates include sodium metasilicate having a molar ratio (SiO ₂ / Na ₂ O) of 1.0, sodium orthosilicate having a molar ratio (SiO ₂ / Na ₂ O) of 0.5, and the like. Especially preferred is sodium metasilicate having a molar ratio (SiO ₂ / Na ₂ O) of 1.0.
In the present invention, examples of the silicate include sodium metasilicate (manufactured by Occidental Chemical Co., Ltd., trade name: anhydrous sodium metasilicate, molar ratio (SiO ₂ / Na ₂ O) = 1.0), sodium orthosilicate. Commercial products such as (manufactured by Nippon Chemical Industry Co., Ltd., trade name: granular ortho, molar ratio (SiO ₂ / Na ₂ O) = 0.5) can be used.

  (D) Content of the silicate of a component is 1-3 mass% when the whole cleaning agent is 100 mass%, and it is preferable that it is 1.02-2.04 mass%. When the content of the silicate is 1% by mass or more, the anticorrosion property is high, and when it is 3% by mass or less, the liquid stability that can be a high concentration liquid can be secured.

[(E) component: Alkali metal hydroxide]
The alkali metal hydroxide (E) is for improving the liquid stability.
Examples of the alkali metal include lithium, sodium, potassium, rubidium, and cesium.

  The content of the alkali metal hydroxide as the component (E) is 2 to 6% by mass, preferably 2.5 to 5.0% by mass when the entire cleaning agent is 100% by mass. When the content of the alkali metal hydroxide is 2% by mass or more and 6% by mass or less, it is possible to ensure liquid stability that can be a high concentration liquid.

  In the cleaning agent of the present invention, the molar ratio (C / E) between the component (C) and the component (E) is 0.5 to 2.0, and preferably 0.7 to 1.2. When the molar ratio of the component (C) and the component (E) is 0.5 or more and 2.0 or less, the liquid stability that can make a high concentration liquid can be secured.

[Other ingredients]
Moreover, the cleaning agent of the present invention may contain an antifoaming agent, a preservative, an aminocarboxylic acid chelating agent and the like as optional components. Among these, since the detergency becomes higher, it is preferable to contain an aminocarboxylic acid chelate.
Examples of aminocarboxylic acid chelating agents include ethylenediaminetetraacetic acid (EDTA), triethylenetetraacetic acid (TTHA), methylglycine diacetic acid (MGDA), 1,3-propane-2-diaminetetraacetic acid (PDTA), hydroxy Ethylethylenediaminetriacetic acid (HEDTA), hydroxyethyliminodiacetic acid (HIDA), nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTPA), propylenediaminetetraacetic acid, triethylenetetraaminehexaacetic acid, ethylene glycol dietherdiaminetetraacetic acid, Acids such as ethylenediaminetetrapropionic acid, cyclohexane-1,2-diaminetetraacetic acid, iminodisuccinic acid, aspartic acid diacetic acid, β-alanine diacetic acid, hydroxyiminodisuccinic acid, etc. It can be mentioned a salt thereof.
Examples of the base for forming a salt include sodium, potassium, calcium, magnesium and the like.
The content of the aminocarboxylic acid chelating agent can be appropriately selected according to the purpose within a range not impairing the effects of the present invention.

[PH]
The pH of the cleaning agent at 25 ° C. is preferably in the range of 11.4 to 11.8. If the pH of the cleaning agent is 11.4 or higher, the cleaning properties are higher, and if the pH is 11.8 or lower, the corrosion resistance of metals (especially amphoteric metals such as aluminum) is higher.
In order to achieve the above pH, an alkali or an acid may be added. Examples of the alkali include inorganic alkali agents such as sodium hydroxide and potassium hydroxide, and organic alkalis such as alkanolamines and quaternary ammonium hydroxy compounds. Examples of the acid include inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid, and organic acids such as acetic acid.

[Dilution of cleaning agent]
Prior to use, the cleaning agent may be appropriately diluted according to the object to be cleaned.
When the object to be cleaned is a metal automobile part, it is preferably diluted to 0.3 to 15 mass, more preferably 0.5 to 5.0 mass%. If the dilution concentration is 0.3% by mass or more, sufficient detergency, anticorrosiveness and foam suppression can be obtained.
As the solvent for dilution, water is preferable because of excellent handleability.

[Production method]
There is no restriction | limiting in particular as a manufacturing method of cleaning agent, According to the objective, it can select suitably, For example, (A) component, (B) component, (C) component, (D) component, and (E) component If necessary, it can be produced by mixing other components and a solvent. More specifically, for example, (A) component, (B) component, (C) component, (D) component, (E) component, and other components as necessary are added to the solvent, It can manufacture by stirring at 10-30 degreeC. There is no restriction | limiting in particular as an apparatus used for stirring, According to the objective, it can select suitably, For example, a stirring bar, a stirring blade, etc. can be utilized.
There is no restriction | limiting in particular as a solvent, Although it can select suitably according to the objective, Since it is excellent in handleability, water is preferable.

By containing the five components (A) to (E) in the above range, the cleaning agent of the present invention exhibits high detergency against metals, anticorrosion, and anti-discoloration and is excellent in foam suppression. Moreover, it is excellent in liquid stability when a high concentration liquid is used. By increasing the concentration, production costs and transportation costs can be reduced.
Since the cleaning agent of the present invention is particularly excellent in the cleaning performance of cutting waste and cutting oil, it is suitably used for cleaning metal parts for automobiles in which cutting scrap and cutting oil are often attached.

  In order to form the component (A) (nonionic surfactant) used in Examples and Comparative Examples in Table 1, the component (B) (amine compound) in Table 2, and the component (C) (carboxylate) Table 3 shows the carboxylic acid, Table 4 shows the component (D) (silicate), and Table 5 shows the component (E) (alkali metal hydroxide).

(Examples 1-22, Comparative Examples 1-15)
Each component was mixed with the formulation shown in Tables 6 to 9 to prepare each of the cleaning agents. In addition, the unit of the compounding quantity of Tables 6-9 is "mass%", and all components show the amount of pure components conversion.
The liquid detergent, detergency, anticorrosiveness, and antifoaming property of the obtained detergent were evaluated as follows. For the detergency, anticorrosion and antifoaming properties, the obtained detergent was diluted to 1% by mass.

<Liquid stability>
After preparing the cleaning agent, the liquid stability was evaluated by observing the state after one month in an environment of room temperature, 40 ° C. and −5 ° C.
(Evaluation methods)
Appearance observation: The appearance of the liquid was observed to examine the presence of precipitates and liquid separation.
(Evaluation criteria)
A: No precipitate or liquid separation was observed under any environment of room temperature, 40 ° C., and −5 ° C.
○: Precipitates and liquid separation were not observed in a room temperature environment, but precipitates and liquid separation were observed in a 40 ° C. and −5 ° C. environment.
Δ: Precipitates and liquid separation occurred under any environment of room temperature, 40 ° C., and −5 ° C.
X: Precipitates and liquid separation occurred immediately after preparation.
If evaluation is (double-circle) and (circle), it has sufficient liquid stability.

<Detergency>
(Test method)
A water-soluble cutting oil was applied to the ceramic test piece, and aluminum powder was uniformly dispersed, and then heated at 100 ° C. for 1 hour to obtain a test piece for evaluating the cleaning performance.
After heating the cleaning liquid which diluted the obtained cleaning agent to 50 degreeC, the test piece was immersed in this. The test piece was washed for 1 minute while stirring the washing liquid at 200 rpm, and then pulled up from the washing liquid. The surface appearance of the pulled up test piece was observed as follows, and the detergency was evaluated.
(Evaluation methods)
Appearance observation: The color of the test piece after washing and that before washing were compared.
Microscopic observation: The surface of the test piece was observed with a microscope, and the size (length of the longest part) and amount of the remaining foreign matter were evaluated.
A: Residual foreign matters could not be confirmed by visual observation, and no residual foreign matters having a size of 50 μm or more were observed by microscopic observation.
○: Foreign matters could not be confirmed by visual observation, but a slight amount of residual foreign matters having a size of 50 μm or more was observed by microscopic observation.
Δ: Foreign matters could not be confirmed by visual observation, but residual foreign matters having a size of 50 μm or more were observed by microscopic observation.
X: It was almost the same as the unwashed test piece.
If evaluation is (double-circle) and (circle), it has sufficient detergency.

<Anti-corrosion>
(Test method)
The surface of the aluminum test piece (aluminum material: A2017P, ADC-12) was polished with a sandpaper to remove the oxide film, immersed in acetone, and the aluminum debris was removed with an ultrasonic cleaner.
The obtained cleaning solution in which the cleaning agent was diluted was heated to 50 ° C., and then the test piece was immersed in this, left for 10 minutes, and then pulled up from the cleaning solution. The surface appearance of the pulled up test piece was compared with the surface appearance of the unwashed test piece, and the anticorrosion property was evaluated as follows from the degree of discoloration and corrosion.
(Evaluation criteria)
(Double-circle): It was not discoloring so that it might not change at all with an unwashed thing.
○: Although it was partially blackish, 80% of the entire surface of the test piece was not discolored.
Δ: Discolored and blackened.
X: Discolored and blackened, and the test piece was rough (corrosion).
If evaluation is (double-circle) and (circle), it has sufficient anti-corrosion property.

<Foam suppression>
30 mL each of the cleaning liquid diluted with the cleaning agent and the water-soluble cutting oil were put into a colorimetric tube, and each colorimetric tube was shaken up and down 30 times to foam. The height of the foam 3 minutes after the end of shaking was measured, and the foam suppression property was evaluated as follows.
(Evaluation criteria)
A: 0 to 5 mm
○: 6 to 10 mm
Δ: 11-20mm
X: 20 mm or more If evaluation is (double-circle) and (circle), it has sufficient foam suppression property.

Examples 1-22 containing a nonionic surfactant having 8 to 11 carbon atoms of R ^{1 in} the general formula (1), an alkyldiamine or an alkyloxoamine, a carboxylate, a silicate, and an alkali metal hydroxide This cleaning agent was excellent in detergency, anticorrosion, anti-discoloration, and antifoaming properties, and also in liquid stability when made into a high concentration liquid.
On the other hand, it contains alkyloxoamine, carboxylate, silicate, and alkali metal hydroxide, but does not contain nonionic surfactant having 8 to 11 carbon atoms of R ^{1 in} the general formula (1). The cleaning agent of Comparative Example 1 had low cleaning properties.
Comparison in which R ¹ of the general formula (1) contains a nonionic surfactant having 8 to 11 carbon atoms, a carboxylate, a silicate, and an alkali metal hydroxide but does not contain an alkyldiamine or an alkyloxoamine. The detergent of Example 2 had low foam suppression.
R ¹ of the general formula (1) contains a nonionic surfactant having 8 to 11 carbon atoms, an alkyloxoamine, a silicate, and an alkali metal hydroxide, but does not contain a carboxylate. The cleaning agent had low liquid stability.
The nonionic surfactant having 8 to 11 carbon atoms of R ^{1 in} the general formula (1), alkyl oxoamine, carboxylate and alkali metal hydroxide, but containing no silicate The cleaning agent had low corrosion resistance.
R ¹ of the general formula (1) contains a nonionic surfactant having 8 to 11 carbon atoms, an alkyloxoamine, a carboxylate and a silicate, but does not contain an alkali metal hydroxide. The cleaning agent had low liquid stability.
In the cleaning agent of Comparative Example 6 in which the content of the nonionic surfactant having 8 to 11 carbon atoms of R ^{1 in} the general formula (1) is less than 5% by mass, the cleaning property was low.
In the cleaning agent of Comparative Example 7 in which the content of the nonionic surfactant having 8 to 11 carbon atoms of R ^{1 in} the general formula (1) exceeds 30% by mass, the liquid stability was low.
The detergent of Comparative Example 8 having an alkyloxoamine content of less than 1% by mass had low foam suppression.
In the cleaning agent of Comparative Example 9 in which the alkyloxoamine content exceeds 10% by mass, the liquid stability was low.
In the cleaning agent of Comparative Example 10 having a carboxylate content of less than 5% by mass and the cleaning agent of Comparative Example 11 having a carboxylate content of more than 20% by mass, the liquid stability was low.
In the cleaning agent of Comparative Example 12 having a silicate content of less than 1% by mass, the anticorrosion property was low.
In the cleaning agent of Comparative Example 13 in which the silicate content exceeds 3% by mass, the liquid stability was low.
The detergent of Comparative Example 14 having an alkali metal hydroxide content of less than 2% by mass and the detergent of Comparative Example 15 having an alkali metal hydroxide content of more than 6% by mass have low liquid stability. It was.

Claims (2)

Component (A): General formula (1) R ¹ O (AO) _n H (wherein R ¹ is an alkyl group or alkenyl group having 8 to 11 carbon atoms, AO is an alkylene oxide, and n is an average addition of AO) A nonionic surfactant represented by the number of moles of 1 to 10, and
Component (B): an amine compound represented by general formula (2) R ² —X— (CH ₂ ) ₃ —NH ₂ (wherein R ² is an alkyl group having 8 to 12 carbon atoms, and X is -O- or -NH-).
Component (C): a carboxylic acid salt having 4 to 10 carbon atoms in total,
(D) component: silicate,
(E) component: containing an alkali metal hydroxide,
The content of the component (A) is 5 to 30% by mass, the content of the component (B) is 1 to 10% by mass, the content of the component (C) is 5 to 20% by mass, and the content of the component (D) is 1 to 3% by mass, and (E) component content is 2 to 6% by mass. The metal cleaning agent according to claim 1, wherein the molar ratio (C / E) of the component (C) and the component (E) is 0.5 to 2.0.